The 15th-ranked Carla Suarez Navarro will now play third-seeded Klara Zakopalova of the Czech Republic.
Kamran Jebreili/AP

FLORIANOPOLIS, Brazil (AP) -- Top-seeded Carla Suarez Navarro advanced to the Brazil Cup semifinals Thursday after No. 5-seeded Monica Niculescu of Romania retired with an apparent right ankle injury.

Niculescu had been struggling to move around the court and at one point lost eight games in a row before pulling out while trailing the Spaniard 4-6, 6-0, 4-1.

The 15th-ranked Navarro will now play third-seeded Klara Zakopalova of the Czech Republic, runner up in the Brazil Open last week. Zakopalova advanced after Alexandra Dulgheru of Romania retired while down 3-6, 2-5.

Second-seeded Garbine Muguruza of Spain beat qualifier Alison Van Uytvanck of Belgium 6-2, 6-7 (1), 6-3 and will next will play Yaroslava Shvedova of Kazakhstan, who defeated sixth-seeded Alexandra Cadantu of Romania 6-3, 6-3.

Copyright 2014 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

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